1. Field the Invention
The present invention relates to a wound core for stationary induction apparatus, more specifically, to a wound core configured with laminated ribbons for stationary induction apparatus.
2. Description of the Related Art
As a material of a wound core for a stationary induction apparatus such as a transformer and a reactor, amorphous alloy ribbons have become an alternative for conventionally used silicon steel plates. The amorphous alloy ribbon, which is produced by quenching a melted alloy, has excellent magnetic property such as small iron loss and a magnetic exciting current compared to silicon steel plates.
Due to its production method, an amorphous alloy ribbon has a thickness of approximately 25 to 30 μm, which is smaller than the thickness of a silicon steel plate. Thus a wound core formed of wound amorphous alloy ribbons disadvantageously has low bending stiffness and the core may easily lose shape.
JP-05-347219-A discloses an amorphous wound core having a reinforcing insulator which is formed by applying an adhesive to a leg to magnetize or an edge face of all layers and then placing an insulating paper on the applied adhesive.
In the amorphous wound core disclosed in JP-05-347219-A, the innermost layer and the outermost layer of the laminated core are each provided with a reinforcing frame. The leg is reinforced and insulated by an insulating paper bonded on an adhesive applied on the leg or the edge face of all layers and further, as required, by an adhesive tape wound around the insulating paper.
According to the technique, a loss of shape of the core caused by its weight can be suppressed to some extent, and this suppression allows production of a transformer of a size that does not necessarily require an external supporting structure.